The present invention relates to a technology which is effective when applied to a contact forming technology in a method of manufacturing a semiconductor integrated circuit device (or semiconductor device).
Patent Document 1 (Japanese Unexamined Patent Publication No. 2001-102345) discloses a technology of easily generating ammonium fluoride by heating ammonia and nitrogen trifluoride and the like at around 700° C., regarding a technology of dry washing for removing a natural oxide film on the silicon surface by vapor phase ammonium fluoride.
Patent Document 2 (Japanese Unexamined Patent Publication No. 2007-214538) or Patent Document 3 (US Patent Application No. 2007-0161218) discloses a technology of removing a natural oxide film on nickel silicide by heating at around 100° C. to 300° C. under a plasma atmosphere of a mixed gas of NF3 gas and a gas containing a hydrogen element such as ammonia before forming a barrier metal film of contact, for lowering contact resistance caused by the natural oxide film and the like on nickel silicide.
Patent Document 4 (International Patent Publication No. WO2005/098913) or Patent Document 5 (US Patent Application No. 2007-0257372) discloses a technology of performing a dry cleaning treatment under a plasma atmosphere of a mixed gas of ammonia gas and hydrogen fluoride gas before forming a barrier metal film of contact, for lowering contact resistance caused by a natural oxide film and the like on nickel silicide.
Patent Document 6 (Japanese Unexamined Patent Publication No. 2007-281298) or Patent Document 7 (US Patent Application No. 2007-0238321) discloses a technology of removing a natural oxide film of the silicon surface under a remote plasma atmosphere in a mixed gas of NF3 gas and ammonia and the like before forming a nickel film, as a dry cleaning method before the formation of nickel silicide.
Patent Document 8 (Japanese Unexamined Patent Publication No. 2007-311540) or Patent Document 9 (US Patent Application No. 2007-0269976) discloses a technology of removing a natural oxide film on nickel silicide under a remote plasma atmosphere in a mixed gas of NF3 gas and a gas containing a hydrogen element such as ammonia before forming a barrier metal film of contact, for lowering contact resistance caused by the natural oxide film and the like on nickel silicide.
Patent Document 10 (Japanese Unexamined Patent Publication No. 2008-311457), Patent Document 11 (US Patent Application No. 2008-0311718), Patent Document 12 (Japanese Unexamined Patent Publication No. 2008-103370), or Patent Document 13 (US Patent Application No. 2008-0176396) discloses a technology of removing a natural oxide film on nickel silicide by a plasma treatment in a mixed gas containing ammonia gas after forming a barrier metal film of contact, for lowering contact resistance caused by the natural oxide film and the like on nickel silicide.